This uses the __kptr* macros as well, and tries to test the stuff that
is supposed to work, since we have negative tests in test_verifier
suite. Also include some code to test map-in-map support, such that the
inner_map_meta matches the map value of map added as element.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
---
.../selftests/bpf/prog_tests/map_kptr.c | 20 ++
tools/testing/selftests/bpf/progs/map_kptr.c | 236 ++++++++++++++++++
2 files changed, 256 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/map_kptr.c
create mode 100644 tools/testing/selftests/bpf/progs/map_kptr.c
diff --git a/tools/testing/selftests/bpf/prog_tests/map_kptr.c b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
new file mode 100644
index 000000000000..688732295ce9
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+
+#include "map_kptr.skel.h"
+
+void test_map_kptr(void)
+{
+ struct map_kptr *skel;
+ char buf[24];
+ int key = 0;
+
+ skel = map_kptr__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "map_kptr__open_and_load"))
+ return;
+ ASSERT_OK(bpf_map_update_elem(bpf_map__fd(skel->maps.hash_map), &key, buf, 0),
+ "bpf_map_update_elem hash_map");
+ ASSERT_OK(bpf_map_update_elem(bpf_map__fd(skel->maps.hash_malloc_map), &key, buf, 0),
+ "bpf_map_update_elem hash_malloc_map");
+ map_kptr__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/map_kptr.c b/tools/testing/selftests/bpf/progs/map_kptr.c
new file mode 100644
index 000000000000..0b6f60423219
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/map_kptr.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+
+struct map_value {
+ struct prog_test_ref_kfunc __kptr *unref_ptr;
+ struct prog_test_ref_kfunc __kptr_ref *ref_ptr;
+ struct prog_test_ref_kfunc __kptr_percpu *percpu_ptr;
+ struct prog_test_ref_kfunc __kptr_user *user_ptr;
+};
+
+struct array_map {
+ __uint(type, BPF_MAP_TYPE_ARRAY);
+ __type(key, int);
+ __type(value, struct map_value);
+ __uint(max_entries, 1);
+} array_map SEC(".maps");
+
+struct hash_map {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+ __type(key, int);
+ __type(value, struct map_value);
+ __uint(max_entries, 1);
+} hash_map SEC(".maps");
+
+struct hash_malloc_map {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __type(key, int);
+ __type(value, struct map_value);
+ __uint(max_entries, 1);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+} hash_malloc_map SEC(".maps");
+
+struct lru_hash_map {
+ __uint(type, BPF_MAP_TYPE_LRU_HASH);
+ __type(key, int);
+ __type(value, struct map_value);
+ __uint(max_entries, 1);
+} lru_hash_map SEC(".maps");
+
+#define DEFINE_MAP_OF_MAP(map_type, inner_map_type, name) \
+ struct { \
+ __uint(type, map_type); \
+ __uint(max_entries, 1); \
+ __uint(key_size, sizeof(int)); \
+ __uint(value_size, sizeof(int)); \
+ __array(values, struct inner_map_type); \
+ } name SEC(".maps") = { \
+ .values = { [0] = &inner_map_type }, \
+ }
+
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_ARRAY_OF_MAPS, array_map, array_of_array_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_ARRAY_OF_MAPS, hash_map, array_of_hash_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_ARRAY_OF_MAPS, hash_malloc_map, array_of_hash_malloc_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_ARRAY_OF_MAPS, lru_hash_map, array_of_lru_hash_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_HASH_OF_MAPS, array_map, hash_of_array_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_HASH_OF_MAPS, hash_map, hash_of_hash_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_HASH_OF_MAPS, hash_malloc_map, hash_of_hash_malloc_maps);
+DEFINE_MAP_OF_MAP(BPF_MAP_TYPE_HASH_OF_MAPS, lru_hash_map, hash_of_lru_hash_maps);
+
+extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp) __ksym;
+extern struct prog_test_ref_kfunc *
+bpf_kfunc_call_test_kptr_get(struct prog_test_ref_kfunc **p, int a, int b) __ksym;
+extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
+
+static __always_inline
+void test_kptr_unref(struct map_value *v)
+{
+ struct prog_test_ref_kfunc *p;
+
+ p = v->unref_ptr;
+ /* store untrusted_ptr_or_null_ */
+ v->unref_ptr = p;
+ if (!p)
+ return;
+ if (p->a + p->b > 100)
+ return;
+ /* store untrusted_ptr_ */
+ v->unref_ptr = p;
+ /* store NULL */
+ v->unref_ptr = NULL;
+}
+
+static __always_inline
+void test_kptr_ref(struct map_value *v)
+{
+ struct prog_test_ref_kfunc *p;
+
+ p = v->ref_ptr;
+ /* store ptr_or_null_ */
+ v->unref_ptr = p;
+ if (!p)
+ return;
+ if (p->a + p->b > 100)
+ return;
+ /* store NULL */
+ p = bpf_kptr_xchg(&v->ref_ptr, NULL);
+ if (!p)
+ return;
+ if (p->a + p->b > 100) {
+ bpf_kfunc_call_test_release(p);
+ return;
+ }
+ /* store ptr_ */
+ v->unref_ptr = p;
+ bpf_kfunc_call_test_release(p);
+
+ p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
+ if (!p)
+ return;
+ /* store ptr_ */
+ p = bpf_kptr_xchg(&v->ref_ptr, p);
+ if (!p)
+ return;
+ if (p->a + p->b > 100) {
+ bpf_kfunc_call_test_release(p);
+ return;
+ }
+ bpf_kfunc_call_test_release(p);
+}
+
+static __always_inline
+void test_kptr_percpu(struct map_value *v)
+{
+ struct prog_test_ref_kfunc *p;
+
+ p = v->percpu_ptr;
+ /* store percpu_ptr_or_null_ */
+ v->percpu_ptr = p;
+ if (!p)
+ return;
+ p = bpf_this_cpu_ptr(p);
+ if (p->a + p->b > 100)
+ return;
+ /* store percpu_ptr_ */
+ v->percpu_ptr = p;
+ /* store NULL */
+ v->percpu_ptr = NULL;
+}
+
+static __always_inline
+void test_kptr_user(struct map_value *v)
+{
+ struct prog_test_ref_kfunc *p;
+ char buf[sizeof(*p)];
+
+ p = v->user_ptr;
+ /* store user_ptr_or_null_ */
+ v->user_ptr = p;
+ if (!p)
+ return;
+ bpf_probe_read_user(buf, sizeof(buf), p);
+ /* store user_ptr_ */
+ v->user_ptr = p;
+ /* store NULL */
+ v->user_ptr = NULL;
+}
+
+static __always_inline
+void test_kptr_get(struct map_value *v)
+{
+ struct prog_test_ref_kfunc *p;
+
+ p = bpf_kfunc_call_test_kptr_get(&v->ref_ptr, 0, 0);
+ if (!p)
+ return;
+ if (p->a + p->b > 100) {
+ bpf_kfunc_call_test_release(p);
+ return;
+ }
+ bpf_kfunc_call_test_release(p);
+}
+
+static __always_inline
+void test_kptr(struct map_value *v)
+{
+ test_kptr_unref(v);
+ test_kptr_ref(v);
+ test_kptr_percpu(v);
+ test_kptr_user(v);
+ test_kptr_get(v);
+}
+
+SEC("tc")
+int test_map_kptr(struct __sk_buff *ctx)
+{
+ void *maps[] = {
+ &array_map,
+ &hash_map,
+ &hash_malloc_map,
+ &lru_hash_map,
+ };
+ struct map_value *v;
+ int i, key = 0;
+
+ for (i = 0; i < sizeof(maps) / sizeof(*maps); i++) {
+ v = bpf_map_lookup_elem(&array_map, &key);
+ if (!v)
+ return 0;
+ test_kptr(v);
+ }
+ return 0;
+}
+
+SEC("tc")
+int test_map_in_map_kptr(struct __sk_buff *ctx)
+{
+ void *map_of_maps[] = {
+ &array_of_array_maps,
+ &array_of_hash_maps,
+ &array_of_hash_malloc_maps,
+ &array_of_lru_hash_maps,
+ &hash_of_array_maps,
+ &hash_of_hash_maps,
+ &hash_of_hash_malloc_maps,
+ &hash_of_lru_hash_maps,
+ };
+ struct map_value *v;
+ int i, key = 0;
+ void *map;
+
+ for (i = 0; i < sizeof(map_of_maps) / sizeof(*map_of_maps); i++) {
+ map = bpf_map_lookup_elem(&array_of_array_maps, &key);
+ if (!map)
+ return 0;
+ v = bpf_map_lookup_elem(map, &key);
+ if (!v)
+ return 0;
+ test_kptr(v);
+ }
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.35.1
